1. Field of the Invention
This invention relates generally to vehicle repair apparatus, and is more particularly concerned with means for tilting a repair rack during the raising of the rack above the floor.
2. Discussion of the Prior Art
Apparatus for repairing automotive vehicles following a collision typically includes a platform onto which the vehicle is loaded. The platform is subsequently raised above the floor level to have the vehicle at a convenient height for the work of straightening the vehicle. In raising the platform, the most common means is to provide a parallel linkage so that the platform is raised uniformly, and is level at all times.
The parallel linkage works well under most conditions, and such apparatus has been commercially successful: see for example U.S. Pat. No. 5,027,639. Using the parallel linkage, the platform is level on the floor, and the platform remains level as the platform is raised to any desired height. Other prior art apparatus utilizes separate fluid operated cylinders on each of the four legs supporting the platform; and, while such an arrangement works, it is more expensive than the use of one cylinder with mechanical linkages as in the cited patent.
In recent times, a number of automobiles are being made very low, so the undercarriage is close to the ground. It has been found that, in loading such a vehicle onto the prior art racks, the cars tend to "bottom out" as they move onto the platform. The lowest such a platform will go is flat on the floor, so there is no means for preventing the bottoming out, and consequent potential damage to the vehicle.